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:c:type:`uv_fs_poll_t` --- FS Poll handle

deps/uv/docs/src/fs_poll.rst

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.. _fs_poll:

:c:type:uv_fs_poll_t --- FS Poll handle

FS Poll handles allow the user to monitor a given path for changes. Unlike :c:type:uv_fs_event_t, fs poll handles use stat to detect when a file has changed so they can work on file systems where fs event handles can't.

Data types

.. c:type:: uv_fs_poll_t

FS Poll handle type.

.. c:type:: void (uv_fs_poll_cb)(uv_fs_poll_t handle, int status, const uv_stat_t* prev, const uv_stat_t* curr)

Callback passed to :c:func:`uv_fs_poll_start` which will be called repeatedly
after the handle is started, when any change happens to the monitored path.

The callback is invoked with `status < 0` if `path` does not exist
or is inaccessible. The watcher is *not* stopped but your callback is
not called again until something changes (e.g. when the file is created
or the error reason changes).

When `status == 0`, the callback receives pointers to the old and new
:c:type:`uv_stat_t` structs. They are valid for the duration of the
callback only.

Public members ^^^^^^^^^^^^^^

N/A

.. seealso:: The :c:type:uv_handle_t members also apply.

API

.. c:function:: int uv_fs_poll_init(uv_loop_t* loop, uv_fs_poll_t* handle)

Initialize the handle.

.. c:function:: int uv_fs_poll_start(uv_fs_poll_t* handle, uv_fs_poll_cb poll_cb, const char* path, unsigned int interval)

Check the file at `path` for changes every `interval` milliseconds.

.. note::
    For maximum portability, use multi-second intervals. Sub-second intervals will not detect
    all changes on many file systems.

.. c:function:: int uv_fs_poll_stop(uv_fs_poll_t* handle)

Stop the handle, the callback will no longer be called.

.. c:function:: int uv_fs_poll_getpath(uv_fs_poll_t* handle, char* buffer, size_t* size)

Get the path being monitored by the handle. The buffer must be preallocated
by the user. Returns 0 on success or an error code < 0 in case of failure.
On success, `buffer` will contain the path and `size` its length. If the buffer
is not big enough `UV_ENOBUFS` will be returned and `size` will be set to
the required size.

.. versionchanged:: 1.3.0 the returned length no longer includes the terminating null byte,
                    and the buffer is not null terminated.

.. versionchanged:: 1.9.0 the returned length includes the terminating null
                    byte on `UV_ENOBUFS`, and the buffer is null terminated
                    on success.

.. seealso:: The :c:type:uv_handle_t API functions also apply.